void ChangeSelection(Action a)
{
state = GridViewSelectionState.SelectionChanging;
a(); // Causes GridView.OnSelectionChanged to trigger which calls SuppressSelectionChanged which returns true.
state = GridViewSelectionState.SelectionChanged;
gridView.OnSelectionChanged(EventArgs.Empty); // Calls SuppressSelectionChanged which returns false.
state = GridViewSelectionState.Normal; // This should already be done in SuppressSelectionChanged but repeated for robustness
}
/// <summary>
/// Initializes a new instance of the <see cref="Eto.Forms.GridViewSelection"/> class.
/// </summary>
/// <param name="gridView">Grid view associated with the selection object</param>
/// <param name="dataStore">Data store to iterate</param>
public GridViewSelection(GridView gridView, IDataStore dataStore)
{
this.gridView = gridView;
this.selectedRows = new SortedSet<int>();
this.state = GridViewSelectionState.Normal;
var collection = dataStore as INotifyCollectionChanged;
if (collection != null)
collection.CollectionChanged += OnCollectionChanged;
}
/// <summary>
/// Resets the selection to the specified model indexes.
/// Called by
/// a) SelectionPreserver.Dispose() during sort and filter operations
/// b) OnCollectionChanged when the model collection is changed.
/// </summary>
private void ResetSelection(SortedSet<int> newSelectedRows,
HashSet<object> selectedItems = null,
HashSet<object> removedSelectedItems = null)
{
state = GridViewSelectionState.SelectionChanging; // causes selection events to be suppressed.
// Set the selection model indexes
selectedRows.Clear();
foreach (var i in newSelectedRows)
selectedRows.Add(i);
// Create the set of selected items if it wasn't supplied
if (selectedItems == null)
{
selectedItems = new HashSet<object>();
foreach (var i in selectedRows)
selectedItems.Add(DataStoreView.Model[i]);
}
// Calculate the view indexes
var view = DataStoreView.View;
var selectedRowViewIndexes = new SortedSet<int>();
for (var i = 0; i < view.Count; ++i) // O(nlogn)
if (selectedItems.Contains(view[i]))
selectedRowViewIndexes.Add(i);
// Reselect the rows in the handler.
Handler.UnselectAll();
foreach (var i in selectedRowViewIndexes)
Handler.SelectRow(i);
state = GridViewSelectionState.Normal; // start firing selection changed events again.
// TODO: should we fire SelectionChanged events if
// selected items were removed? This is an edge case;
// implement only if needed.
}
